Apparatus for winding sheet material

ABSTRACT

Two parallel spaced rollers form a nip or seat in engagement with which the sheet material is wound on a roll rod. A roll rod guide is at each end of the roller pair and is pivotable with the downstream roller to move a roll rod between a rolling position in the nip, a cutting position and a discharge position. Moveable cutting means are coupled to the roller drive and cut the sheet in the vicinity of the nip.

' United States Patent 1 swarm s4 APPARATUS For: wuvnmo SHEE'ITMATERIAL 25 Claims, 6 Drawing Figs.

[52] U.S. Cl 242/56 [51] Int. Cl B65h 35/04 [50] Field of Search 242/56 [56] References Cited UNITED STATES PATENTS 2,682,379 6/1954 Piper et al 242/56 Primary Examiner-Nathan L. Mintz AttameyMilton Robert Kestenbaum ABSTRACT: Two parallel spaced rollers form a nip or seat in engagement with which the sheet material is wound on a roll rod. A roll rod guide is at each end of the roller pair and is pivotable with the downstream roller to move a roll rod between a rolling position in the nip, a cutting position and a discharge position. Moveable cutting means are coupled to the roller drive and cut the sheet in the vicinity of the nip.

PATENTEU MAR 2197! SHEET 2 OF 6 INVENTOR. BY c/u'kawDfivB/zm/ W K ML PATENTEMAR 21am 3567,1 14

SHEET u 0F 6 INVENTOR. Jam 01 @MMW 1/ f. map-W PATENTEUHAR 219?: 3,567,144

SHEET 5 UF 6 IN VEN TOR. c/d'em) Mam PATENTEUMR 21971 3557.144

SHIN G N G INVENTOR. W c/u" M Mew/w APPARATUS FOR WINDING SHEET MATERIAL The invention relates to an apparatus for winding sheet material and is directed to means for the continuous changing of rolls. The apparatus, which may be a textile web treating machine, is of the type comprising two parallel spaced rollers which form a nip or seat in engagement with which the sheet material is wound on a roll rod.

One form of such apparatus has already been proposed in which a roll can be completely wound in the nip of two rollers rigidly mounted in the apparatus and guided downwards over the roller nearest to the end of the apparatus by means of the roll rod guide, until the roller comes into contact with two more rollers, whereupon the roll and the web of material are both out off in the same position. ln accordance with this proposal the first two rollers mentioned are rigid and the device for guiding the roll rod guide involves considerable expense. In addition two curved tracks and four carriages are used, two of which must be capable of being coupled together or uncoupled in fixed positions. Furthermore, the whole magazine in this embodiment is movable, which presents rather difficult kinematic problems. Firstly the drive for the cutting wire has no connection with the speed at which the web is transported and therefore cutting problems occur. Moreover, the entire embodiment as proposed is relatively costly.

Another such apparatus is known in which winding or rolling in the nip is impossible, i.e. where no hard rolls can be produced, which is of great importance to webs of synthetic material. The roll is no longer in contact with this first roller over the last metres before the web is cut off; therefore no satisfactory rolls-are produced. The movement of the roll when it falls off this first roller and moves past the cutting position to the discharge position is inadequately controlled. Finally the speed of the rapid cutting wire in this embodiment has no connection with speed at which the web is transported.

The aim of the invention is to provide an apparatus in which firstly winding is possible in the nip, secondly in which the movement of the roll can be constantly controlled from the rolling position in the nip to the rolloff position, and, thirdly, in which the roll can remain in constant contact with one roller unless the web of material has already been cut off.

This problem is solved by the invention in accordance with which there is provided apparatus for winding sheet material of the type comprising two parallel spaced rollers which form a nip or seat in engagement with which the sheet material is wound on a roll rod, the apparatus comprising a roll rod guide at each end of the roller pair for engaging respective ends of a roll rod, the guide being pivotable about a fixed axis to move an engaged roll rod between a rolling position in the nip, a cutting position and a discharge position, at least one of the said rollers being pivotable simultaneously with the roll rod guide to enable the rolls to be changed continuously.

It is advantageous if the downstream roller in the direction of sheet travel is pivotable and the shaft of the other roller is mounted in fixed bearings. Then only one roller needs to be moved and no additional apparatus is required on which a new roll rod can be wound from the magazine, until the two rollers return to their winding position in the nip.

It is advantageous if the pivot axis of the roll rod guide is also that of the pivoted roller. In this way the construction of the apparatus is considerably simplified.

It is expedient if the roll rod guide and the pivoted roller are arranged to maintain their relative position. The roll rod guide and the roller can then be mounted on rigid members opposite one another, whereupon the embodiment is once more considerably simplified.

It is expedient if the pivoted roller is mounted for pivoting on a driven shaft lying parallel to the rollers. This enables the pivotable drive roller to be driven continuously and simply despite its pivoting movement.

It is advantageous if the pivoted roller is mounted to the said driven shaft. The drive shaft can thereby be doubly exploited, namely, as a means for supporting the roller and roll rod guide and as a drive for the roller.

It is advantageous if a pivotable bearing plate or bracket for the pivoted roller is mounted at each end of the driven shaft and rigidly connected by an axle lying parallel to the driven shaft and wherein two axially slidable plates for bearing the roll rod guides are provided adjacent respective ends of the said axle. It is then possible to adapt the length of the roller to that of the longest roll rod, while the distance between the two bearing plates and the roll rod guide can be adapted to the variable length of the roll rods without complicating the pivotmg maneuver Preferably there is provided at least one actuator, the piston rod of which is pivotably secured to a said bearing plate, the actuator being pivotally mounted in the apparatus.

It is expedient if the pivoted roller is in a lower position than the first and lies in front of and opposite the first in conventional manner. In this way the second (pivoted) roller can bear the principal load of the roll on the one hand and a firm roll is therefore obtained. On the other hand, the roll for the first roller becomes larger and the magazine holding the roll rods moves nearer to the operator, because the roll rod guide needs to be inclined to the vertical on account of the steps described above, and the roll rod falls more easily into its guide.

A preferred embodiment of the invention is hereafter more particularly described with reference to the accompanying drawings, in which:

FIG. 1 shows a rear view of the apparatus according to the invention, looking in the direction in which the web is transported, with the first roller indicated by broken lines, but without the magazine holding the roll rods and guideway,

FIG. 2 shows a section along the line 2-2 of FIG. 1 with a magazine and a roll rod guide in the roll position in the wedge, as in FIG. 1,

FIG. 3 shows the same view as FIG. 2, but in the cutting position,

FIG. 4 shows the same view as FIG. 2, but in the rolloff position,

FIG. 5 shows a detailed view of one stage in the cutting position when the cutting wire support is in its first position, and

FIG. 6 shows a view according to FIG. 5, of the beginning of a web of material being wound on.

According to FIG. 1 a base or floor 11 supports a lower right-hand machine frame 12, a lower left-hand frame 13, an upper right-hand frame 14 and an upper left-hand frame 16. All these frames are fixed. A first roller 17 is rotatably and drivably mounted in the machine frames 14 and 16. In addition, the ends of a hollow magazine support rod 18 are each secured to the machine frames 14 and 16, which support rod 18 axially and slidably bears a magazine 19, to be described later, for roll rods 21 and can therefore be adapted to the length of the roll rods. The two ends of a drive shaft 22 comprising two separate shafts are mounted in the lower machine frames 12 and 13, which shafts can be telescoped to improve the assembly of devices to be described later. The rotatable drive shaft 22 carries two bearing plates 26 and 27. Two potshaped bearings 28, 29 fixed in the lower machine frame 12 and 13 also assist in the bearing. To the right of the pot-shaped bearing 2% a sleeve or bush 31 is keyed on the drive shaft 22 and bears a sprocket wheel 32. The sleeve 31 is followed by a bearing 33 for the bearing plate 26. The bearing 33 does not rotate with the drive shaft.

To the left of the pot-shaped bearing 29 there is a spacer bush 34 which does not rotate with the drive shaft 22 and on which a bearing 36 is clamped for the bearing plate 27. To the left of the bearing plate 27 there is also an adjusting or setting ring 37. This arrangement ensures that the bearing plates 26, 27 are not moved axially of the drive shaft 22, but can in fact be pivoted about the latter in a manner to be described later.

The bearing plates 26, 27 are rigidly connected by a rod 38 for supporting the roll rod guide.

The bearing plates 26, 27 serve principally to bear a second roller 41 which is seen in the direction of transporting a textile web 39 (FIGS. 2, 3, and is rotatably mounted by bearings 42 and 43.

The second roller 41 is driven by the already-mentioned sprocket wheel 32, an unshown chain and a sprocket wheel 44 which is nonrotatably mounted on the left-hand end of a shaft 46, as shown in FIG. 1. A chain tensioner 47 fastened to the bearing plate 26 is used to tighten thechain. The transmission ratios are selected so that the second roller 41 rotates slightly faster than the first 17. Two identical bearing plates 49, the spacing of which can be varied after clamping bearings 48 are released and adapted to the length of the roll rods 21, are clamped on the support rod 38 by means of the clamping bearings 48.

The following description (FIGS. 26) is confined to the left-hand bearing plate shown in FIG. 1 and the magazine.

An edge 51 of a recess in the bearing plate 49 runs closely around the second roller 41 and extends upwards some distance so that there is provided a good possibility for securing a roll rod guide 52. The latter is rigidly attached to the bearing plate 49 and comprises a U-shaped section, the upper end of which is open. The side 53 facing the magazine 19 is provided with an opening 54. Its end facing a nip 56 (FIG. 2) is closed by a transverse wall 57 of hook-shaped design. As seen in FIG. 2, the hook-shaped end follows approximately the periphery of the first roller 17. As can also be seen in this FIG, the roll rod guide 52 is located perpendicularly to the line connecting the geometrical longitudinal axes of the rollers 17 and 41.

A compression member 58 is rigidly attached to the top of the bearing plate 49 and its free end bears a roller 59. The length of the compression member 58 can be varied by means ofa screw device 61.

As already mentioned, the magazine 19 has another com ponent arranged symmetrically as mirror image of the component shown. The magazine component 19 shown in the FIGS. is rigidly clamped on the support rod 18 by a bearing 62. A guideway 63 having two separate tracks 64 and 66 is attached to the clamping bearing 62. The L-shaped track 64 consisting of U-shaped sections is rigidly connected to the clamping bearing 62 and has openings 67 and 68 in both walls of the U-shaped section. The upper end of the track 64 shown in FIG. 2 is inclined so that empty roll rods 21 can be easily inserted from right to left. The lower end of the track 64 also has an inclined edge 69 (FIG. 3), in the vicinity of which there is provided a rocker bearing 71 for a plate 72 which is not shown in FIGS. 5 and 6. Plate 72 acts as a metering device. The track 66 is rigidly secured on this plate 72 and therefore rockably mounted opposite the track 64. The plate 72 is provided with a stop arm 73 as well as two teeth 74 and 76 which are rigidly fastened to the plate 72 in the indicated position and spaced apart by a distance slightly greater than the external diameter of the ends 77 of the roll rods 21. In the position shown in FIG. 2 the tooth 76 projects vertically into the track 64, whereas in the position shown in FIG. 3, the tooth 74 projects vertically into the track 64. The openings 67 and 68 enable the teeth to move into the track.

As can be seen in the FIGS. the track 66 passes into a bend 78 which ends near the first roller 17 in the position shown in FIG. 3.

A compression spring 79 shown by broken lines engages on the stop arm 73, while the other end of said spring is supported on the bearing 62 and passes through part of the length of a sleeve 81 which is rigidly connected to the bearing 62. The ends of piston rods 82 associated with cylinders 83 or 84 engage pivotably on the two bearing plates 26 and 27. The lower end of the cylinder is also rigidly mounted on the apparatus and pivotably secured at 86 or 87. Finally a support 88 for the cutting wire is provided in the form of a frame. In order to guide the latter a U-shaped section 89 extends between the lower machine frames 12 and 13 and is rigidly connected thereto. Two pilot bushes 91, 92 are also rigidly connected to the U-shaped section 89 and they move guide rods 93, 94 vertically up and down. Their lower ends are rigidly connected by an L-shaped section 96 and their upper ends by an L-shaped section 97. As seen in FIG. 1, toothed racks 98 and 99 also rigidly connected to the L-shaped sections 96, 97 and extending vertically upwards are located behind the guide rods 93, 94. The racks mesh with pinions 101 nonrotatably mounted on a second drive shaft 102 which can be coupled to the first drive shaft 22 via an electromagnetic coupling 103. Plates 104 are screwed firmly on the upper ends of the toothed racks 98, 99 and are rigidly connected by a box section 106. The top side of the box section 106 bears a heat-insulating layer 107 as well as two tension plates 108 and 109 for a cutting wire 111, the ends of which are connected via electrical wiring 112 and 113 to a source of voltage and in addition bear nuts 114 or 116. Compression springs 117, 118 shown by dotted lines in FIG. 1, which hold the cutting wire 111 under constant ten sion, are inserted between these nuts 114 or 116 and the tension plates 108 or 109 respectively. Finally the box section 106 also bears two supports 119 for the cutting wire 111. A second box section 122 on the plate 104 is pivotably mounted about its longitudinal axis by bearings 121 at its ends. This box section 122 is rigidly fastened to a lid or flap 123, which points upwards in the position shown in FIG. 5 and has an inclined edge 124, and is rigidly connected to a lug plate 126 in which a tension spring 127 is hooked by one of its ends, its other end being booked in a block 128 which is rigidly connected to the plate 104.

Furthermore, a pushrod 129 engages pivotably on the lug plate 126, while its other end is connected to a lever 131 which pivots at 132. The pivot lever 131 is provided with a stop 133 rigidly mounted on the lower machine frame 12. Naturally, the same applies to the right-hand side of FIG. 1.

When in use, the apparatus operates as follows:

It should first be assumed that winding or rolling is carried out in the nip 56 as shown in FIG. 2 and that all components are positioned as shown there. The roll 134 has attained its full volume. The magazine 19 is full of roll rods 21, the piston rod 82 is fully extended, the compression member 58 presses the stop arm 73 to the left in opposition to the force of the compression spring 79, and therefore the tooth 76 is located in the first track 64 with a roll rod 21 waiting in front of it. The cutting wire 111 is in its lowest position.

It is now established by unshown means that the time has arrived for changing the roll. The piston rod 82 is then moved downwards relatively slowly, the second roller 41 continues rotating, the web 39 of material is stretched more than before between the two rollers 17 and 41, the compression spring 79 presses the plate 72 into the position shown in FIG. 3, whereupon the tooth 76 moves out of the track 64 and the tooth 74 moves into the track 64. The teeth are of such a length that the tooth 74 has already been pushed between the lowest two roll rods 21 before the tooth 76 releases the lowest roll rod 21. Because of the inclined track and because the track 66 meanwhile forms the precise continuation of the track 64, the lowest roll rod 21 rolls down to the right, is diverted round the bend 78 and slowed down slightly; it then falls onto the web 39 and onto the first roller 17 lying below and begins to rotate.

The electromagnetic clutch 103 is actuated in the position shown in FIG. 3, the second drive shaft 102 rotates and pushes the cutting wire 111 upwards at a speed corresponding to that of the web of material. It is easy to see that in this case the cutting wire 111 remains a relatively long time in that position where it meets the web 39. Good cuts are hereby produced even at web speeds of m./min. Naturally the web 39 is stretched even more during cutting.

Soon after the cutting operation the pivot lever 131 moves against the stop 133 and the lid 123 pivots in a counterclockwise direction to the left as shown in FIG. 6. The first few centimeters after the cut are now located above the upper edge of the lid 123 and during pivoting, are wound to the left by this end around the new roll rod 21. This end falls into the gap between the web ofmaterial and the roll rod 21 so that the first roll is complete. Now the first roller 17 winds on the roll rod 21 held in the bend 78 for a short time, while the piston rod 82 is moved further into the cylinder 83 or 84, whereupon the position shown in FIG. 4 is finally reached, in which the roll rod guide 52 produces an inclined plane from which the roll 134 can drop onto a conveyor 136. The cutting wire support 88 drops downwards on account of its own weight, when no more current is flowing through the electromagnetic clutch 103 and the piston rod 82 travels out again. In the final gradual movements the roll 59 again comes into contact with the stop arm 73 and pivots it to the left. Now the opening 54 is also located below the bend 78, which is pivoted upwards and releases the new roll rod 21, which then falls through the opening 54 into the roll rod guide 52.

During these operations the roll rod 21 which is firstly retained by the tooth 74 then begins to roll again until it is slowed down in its movement by the tooth 76 which is again located in the track 64.

The conditions according to FIG. 2 have thereby been regained with the exception that the roll 134 has only a small diameter and the entire roll rod 21 is located below in the roll rod guide 52. One work cycle is thereby completed.

I claim:

1. Apparatus for winding sheet material of the type comprising two rollers which form a nip or seat in engagement with which the sheet material is wound on a roll rod, the apparatus comprising a roll rod guide at each end of the roller pair, the guide being pivotable about a fixed axis to move an engaged roll rod between a rolling position in the nip, a cutting position and a discharge position, at least one of the said rollers being pivotable simultaneously with the roll rod guide to enable the rolls to be changed continuously.

2. Apparatus as claimed in claim 1 wherein the downstream roller in the direction of sheet travel is pivotable and the shaft of the other roller is mounted in fixed bearings.

3. Apparatus as claimed in claim 1 wherein the pivot axis of the roll rod guide is also that of the pivoted roller.

4. Apparatus as claimed in claim 1 wherein the roll rod guide and the pivoted roller are arranged to maintain their relative position.

5. Apparatus as claimed in claim 1 wherein the pivoted roller pivots about a drive shaft lying parallel to the rollers.

6. Apparatus as claimed in claim 5 wherein the pivoted roller and the roll rod guide are borne by said drive shaft.

7. Apparatus as claimed in claim 6 wherein a pivotable 7' bearing plate for the pivoted roller is mounted at each end of the drive shaft and rigidly connected by an axle lying parallel to the drive shaft and wherein two axially slidable plates for bearing the roll rod guides are provided adjacent respective ends of the said axle.

8. Apparatus as claimed in claim 7 including at least one actuator having a piston rod which is pivotably secured to a said bearing plate, the actuator being pivotally mounted in the apparatus.

9. Apparatus as claimed in claim 1 wherein thepivoted roller is in a lower position than the fixed roller.

closed by transverse walls.

11. Apparatus as claimed in claim 10, wherein the transverse walls are hook-shaped in cross .section.

12. Apparatus asclaimed in claim 10 wherein the magazin has a pair of guideways for receiving respective ends of the roll rods, the outlet of the magazine being located above the nip, the apparatus including a metering device having two teeth which are engageable alternately in said guideway the distance between the teeth being slightly greater than the external diameter of the ends ofthe roll rods.

13. Apparatus as claimed in claim 12 wherein the teeth are located on a common plate which is pivotable about a pivot point located approximately in the path of the longitudinal axis of the roll rods: v

14. Apparatus as claimed in claim 13 wherein the said common plate is resiliently biased by a spring in a direction in which the first tooth, which is further removed from the nip, is located in the guideway, and wherein an actuating device, pivotable with the second roller or the roll rod guide which is arranged in the said rolling position to pivot the plate in opposition to the force of the spring until the first tooth moves out of the guideway and the second tooth moves in.

15. Apparatus as claimed in claim 14 wherein each magazine guideway has two separate tracks, the first of which is rigidly mounted in the apparatus while the second is rigidly fastened to the said common plate, the second track passing into a bend directed towards the fixed roller and ending near thereto.

16. Apparatus as claimed in claim 1 including a cutting means for the sheet material and driving means for said cutting means which is coupled to a drive shaft for said pivotable roller.

17. Apparatus as claimed in claim 16, characterized in that the cutting means are moveable at approximately the same speed as the sheet material being conveyed by the rollers.

18. Apparatus as claimed in claim 16 wherein the cutting means is directed approximately into the nip.

19. Apparatus as claimed in claim 16 wherein on the support means below the cutting means there is provided a lid or flap extending parallel to the drive shaft and which is arranged to bear against said supporting means when in the rolling position in the nip and which is pivotable with its upper edge below the cutting means when the supporting means are moved into the cutting position in the direction of a roll rod lying on the fixed roller.

20. Apparatus as claimed in claim 19 wherein the pivoting position of the lid or flap is a function of the locality of the said supporting means.

21. Apparatus as claimed in claim 20 wherein the lid or flap is connected to a pivot lever in the moving path of which is arranged a stop face rigidly mounted in the apparatus.

22. Apparatus as claimed in claim 19 wherein a resetting spring is provided for the lid or flap.

23. Apparatus as claimed in claim 19 wherein a section of the lid or flap facing'a fresh roll rod lying on the fixed roller is provided with a sloping edge and, when moving upwards, is arranged to make partial or total contact with the roll rod to wrap the cut end of the sheet material around the roll rod.

24. Apparatus as claimed in claim 16 wherein the cutting means comprise a wire.

25. Apparatus as claimed in claim 24 wherein heating means are provided for the wire. 

1. Apparatus for winding sheet material of the type comprising two rollers which form a nip or seat in engagement with which the sheet material is wound on a roll rod, the apparatus comprising a roll rod guide at each end of the roller pair, the guide being pivotable about a fixed axis to move an engaged roll rod between a rolling position in the nip, a cutting position and a discharge position, at least one of the said rollers being pivotable simultaneously with the roll rod guide to enable the rolls to be changed continuously.
 2. Apparatus as claimed in claim 1 wherein the downstream roller in the direction of sheet travel is pivotable and the shaft of the other roller is mounted in fixed bearings.
 3. Apparatus as claimed in claim 1 wherein the pivot axis of the roll rod guide is also that of the pivoted roller.
 4. Apparatus as claimed in claim 1 wherein the roll rod guide and the pivoted roller are arranged to maintain their relative posiTion.
 5. Apparatus as claimed in claim 1 wherein the pivoted roller pivots about a drive shaft lying parallel to the rollers.
 6. Apparatus as claimed in claim 5 wherein the pivoted roller and the roll rod guide are borne by said drive shaft.
 7. Apparatus as claimed in claim 6 wherein a pivotable bearing plate for the pivoted roller is mounted at each end of the drive shaft and rigidly connected by an axle lying parallel to the drive shaft and wherein two axially slidable plates for bearing the roll rod guides are provided adjacent respective ends of the said axle.
 8. Apparatus as claimed in claim 7 including at least one actuator having a piston rod which is pivotably secured to a said bearing plate, the actuator being pivotally mounted in the apparatus.
 9. Apparatus as claimed in claim 1 wherein the pivoted roller is in a lower position than the fixed roller.
 10. Apparatus as claimed in claim 1 including a magazine holding roll rods, wherein each roll guide has a U-shaped section, the limbs standing toward the opposite guide, the limbs on one side facing said magazine and being provided each with an opening at its lower end for receiving fresh roll rods from the magazine, the ends of the guides facing the nip being closed by transverse walls.
 11. Apparatus as claimed in claim 10, wherein the transverse walls are hook-shaped in cross section.
 12. Apparatus as claimed in claim 10 wherein the magazine has a pair of guideways for receiving respective ends of the roll rods, the outlet of the magazine being located above the nip, the apparatus including a metering device having two teeth which are engageable alternately in said guideway the distance between the teeth being slightly greater than the external diameter of the ends of the roll rods.
 13. Apparatus as claimed in claim 12 wherein the teeth are located on a common plate which is pivotable about a pivot point located approximately in the path of the longitudinal axis of the roll rods.
 14. Apparatus as claimed in claim 13 wherein the said common plate is resiliently biased by a spring in a direction in which the first tooth, which is further removed from the nip, is located in the guideway, and wherein an actuating device, pivotable with the second roller or the roll rod guide which is arranged in the said rolling position to pivot the plate in opposition to the force of the spring until the first tooth moves out of the guideway and the second tooth moves in.
 15. Apparatus as claimed in claim 14 wherein each magazine guideway has two separate tracks, the first of which is rigidly mounted in the apparatus while the second is rigidly fastened to the said common plate, the second track passing into a bend directed towards the fixed roller and ending near thereto.
 16. Apparatus as claimed in claim 1 including a cutting means for the sheet material and driving means for said cutting means which is coupled to a drive shaft for said pivotable roller.
 17. Apparatus as claimed in claim 16, characterized in that the cutting means are moveable at approximately the same speed as the sheet material being conveyed by the rollers.
 18. Apparatus as claimed in claim 16 wherein the cutting means is directed approximately into the nip.
 19. Apparatus as claimed in claim 16 wherein on the support means below the cutting means there is provided a lid or flap extending parallel to the drive shaft and which is arranged to bear against said supporting means when in the rolling position in the nip and which is pivotable with its upper edge below the cutting means when the supporting means are moved into the cutting position in the direction of a roll rod lying on the fixed roller.
 20. Apparatus as claimed in claim 19 wherein the pivoting position of the lid or flap is a function of the locality of the said supporting means.
 21. Apparatus as claimed in claim 20 wherein the lid or flap is connected to a pivot lever in the moving path of which is arranged a stop face rigidly mounted in the apparatus.
 22. Apparatus as claimed in claim 19 wherein a resetting spring is provided for the lid or flap.
 23. Apparatus as claimed in claim 19 wherein a section of the lid or flap facing a fresh roll rod lying on the fixed roller is provided with a sloping edge and, when moving upwards, is arranged to make partial or total contact with the roll rod to wrap the cut end of the sheet material around the roll rod.
 24. Apparatus as claimed in claim 16 wherein the cutting means comprise a wire.
 25. Apparatus as claimed in claim 24 wherein heating means are provided for the wire. 